Commercial production of poultry products destined for sale for consumption customarily is carried out in large processing plants. Presently, in many current processing plants, poultry is typically brought in by truck in cages from which the poultry are off-loaded from the truck in the cages and subsequently dumped for further processing. The live poultry are then hung upside-down on a conveyorized shackle line and their heads are dragged through a brine or water bath. They are then stunned using high voltage electricity just prior to being slaughtered.
Hanging the birds while they are still fully awake can be very troublesome, leading to high labor costs and worker injuries. It is not unusual for the birds to flap their wings, causing joint damage and blood clots in the birds, thus degrading the overall quality of the meat and reducing the yield.
Stunning the poultry with gas as part of the processing regimen presents the advantage that the birds are less likely to engage in extensive movement, thereby reducing the burden to the worker and reducing the risk of damage to the bird. However, current gas stunning systems are complicated and expensive. In particular, existing poultry stunning systems often involve high capital costs and require significant changes to the processor's existing infrastructure and operational footprint. In addition, implementation and start-up of the many existing poultry stunning systems at a typical processor site also typically involves significant disruption and downtime of the processor's operation.
Thus, there is a need for a humane controlled atmosphere poultry stunning system capable of improving product quality and minimizing product yield losses, without incurring the complexity and expense of current gas stunning methods and apparatus.